U.S. patent number 6,432,850 [Application Number 09/282,982] was granted by the patent office on 2002-08-13 for fabrics and rust proof clothes excellent in conductivity and antistatic property.
This patent grant is currently assigned to Seiren Co., Ltd.. Invention is credited to Yutaka Matsui, Susumu Takagi.
United States Patent |
6,432,850 |
Takagi , et al. |
August 13, 2002 |
Fabrics and rust proof clothes excellent in conductivity and
antistatic property
Abstract
There are provided fabrics excellent in electrical conductane
and antistatic property as well as dust proof clothes using the
same. Conductive yarn comprising synthetic filament yarn as the
core covered with conductive bicomponent fibers is used as
conductive yarn used in the warps and/or wefts at intervals.
Inventors: |
Takagi; Susumu (Fukui,
JP), Matsui; Yutaka (Fukui, JP) |
Assignee: |
Seiren Co., Ltd. (Fukui,
JP)
|
Family
ID: |
13880708 |
Appl.
No.: |
09/282,982 |
Filed: |
March 31, 1999 |
Foreign Application Priority Data
|
|
|
|
|
Mar 31, 1998 [JP] |
|
|
10-086220 |
|
Current U.S.
Class: |
442/190; 428/373;
442/209; 57/244; 57/243; 57/235; 57/230; 57/210; 442/301; 442/217;
442/208; 442/189; 442/199; 442/200; 442/203; 442/191 |
Current CPC
Class: |
D02G
3/441 (20130101); D03D 15/533 (20210101); Y10T
442/3228 (20150401); Y10T 442/3065 (20150401); Y10T
442/313 (20150401); Y10T 442/3976 (20150401); Y10T
442/3146 (20150401); Y10T 442/3073 (20150401); Y10S
2/901 (20130101); Y10T 442/3081 (20150401); Y10T
442/322 (20150401); Y10T 442/3154 (20150401); Y10T
442/3293 (20150401); Y10T 442/3179 (20150401); Y10T
428/2929 (20150115) |
Current International
Class: |
D02G
3/44 (20060101); D03D 15/00 (20060101); D03D
015/00 (); D02G 003/00 () |
Field of
Search: |
;442/190,191,301,189,203,199,200,208,209,217 ;428/373
;57/210,230,235,243,244 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Morris; Terrel
Assistant Examiner: Ruddock; Ula C.
Attorney, Agent or Firm: Dilworth & Barrese, LLP
Claims
What is claimed is:
1. Woven fabrics comprising warps and/or wefts containing
electrically conductive yarn at intervals, wherein the electrically
conductive yarn is a covered yarn obtained by winding electrically
conductive bicomponent fiber yarn around synthetic filament
yarn.
2. Fabrics according to claim 1 wherein the conductive yarn is
obtained by winding the electrically conductive bicomponent fiber
yarn twice around the synthetic filament yarn.
3. Fabrics according to claim 1 wherein the conductive yarn is
contained in both of the warps and wefts at intervals thereof and
that in one of said warps and wefts the conductive yarn is obtained
by winding the electrically conductive bicomponent fiber twice
around the synthetic filament yarn and in the other of said warps
and wefts the conductive yarn is obtained by winding the conductive
bicomponent fiber once around the synthetic filament yarn.
4. Fabrics according to claim 1 wherein the conductive yarn is
contained in both of the warps and wefts at intervals thereof and
that in one of said warps and wefts the conductive yarn is obtained
by winding the electrically conductive bicomponent fiber twice
around the synthetic filament yarn and in the other of said warps
and wefts the conductive yarn is obtained by double twisting the
synthetic filament yarn with the conductive bicomponent fiber.
5. Fabrics according to claim 1 wherein the conductive bicomponent
fiber comprises carbon, the electrical resistance of said
conductive bicomponent fiber being from about 10.sup.6 to 10.sup.9
.OMEGA./cm.
6. Fabric according to claim 1 wherein the conductive bicomponent
fiber is obtained by bicomponent spinning a non-conductive base
polymer and a matrix polymer containing carbon as a conductive
component such that at least a part of the matrix polymer
containing carbon is exposed to the surface of the fiber.
7. Woven fabrics comprising warps and/or wefts containing
electrically conductive yarn at intervals, wherein the electrically
conductive yarn is a covered yarn obtained by winding electrically
conductive bicomponent fiber yarn around synthetic filament yarn,
wherein the degree of coverage of the conductive bicomponent fiber
in the conductive yarn is 20% to 70%, wherein said degree of
coverage is the percentage of the area of the conductive yarn which
is covered by the conductive bicomponent fiber.
Description
FIELD OF THE INVENTION
The present invention relates to fabrics excellent in conductivity
and antistatic property as well as dust proof clothes sewed
therefrom, which are electroconductive throughout the dust proof
clothes and excellent in durability and antistatic property.
BACKGROUND OF THE INVENTION
Conventionally, yarn composed of electroconductive (hereinafter
referred to "conductive") fibers and non-conductive synthetic
fibers is woven into fabrics for dust proof clothes for a measure
against static electricity. Fabrics into which yarn containing
these conductive fibers has been woven are conductive in the warp
and weft directions along which the conductive fibers have been
woven, not only in the case where yarn containing conductive fibers
is mixed and woven in a striped pattern at predetermined intervals,
but also in the case where the yarn is woven in a check-striped
pattern, but satisfactory conductance cannot be obtained in a
slanting direction of fabric, and therefore, it is difficult to
achieve electrical conductance throughout dust proof fabrics. The
reason for this is that conductive fiber introduced into the warp
and conductive fiber introduced into the weft are in poor
electrical contact with each other.
Further, in dust proof clothes formed from these fabrics, it is
difficult to achieve electrical conductance in the sewn portions,
and it is further difficult to achieve electrical conductance
throughout the dust proof clothes.
The reason is that the conductive yarns in the respective fabrics
are not in electrical contact with each other even in the sewn
portios.
If conductive yarn composed exclusively of conductive fibers is
woven in the case where conductive yarn is woven into fabrics,
differences in fiber characteristics such as strength, elongation,
shrinkage etc. occur between the conductive fibers and other fibers
constituting the fabrics, thus readily causing various drawbacks
such as fiber cutting, puckering etc. at the time of weaving and
processing. Further, because the conductive fibers are more
expensive than general fiber materials, it is also important to
reduce the amount thereof for use.
Accordingly, conductive fibers are mixed with fibers similar to
fibers used in the base constituting fabrics by means of
inter-twisting, air confounding etc., and the yarns thus obtained
are generally used.
In the case where these conductive yarns are mixed in a striped
pattern at predetermined intervals in weaving of fabric, the
resulting fabric is conductive in the direction along which the
conductive fibers have been woven, but cannot be conductive in
other directions.
Further, even in the case where these conductive yarns are woven in
a check-striped pattern at predetermined intervals, there is
electrical conductance in the directions such as warp and weft
directions along which the conductive yarns have been woven, but
the conductive yarns woven into the warp and the conductive yarns
woven into the weft are not in electrical contact with each other,
so it is difficult to achieve satisfactory electrical conductance
in a slanting direction of the fabric, and as a result, it is
difficult to achieve satisfactory electrical conductance throughout
the fabric.
This is caused by the fact that the conductive fibers are buried
inside of the yarn so that the contact between the conductive
fibers inserted into the yarn as the warp and the conductive fibers
inserted into the yarn as the weft is deteriorated.
Further, the conductive fibers are buried inside of the yarn, thus
deteriorating antistatic property and simultaneously raising the
contact resistance between the conductive fibers and the outside,
so the sewn portions in contact under low contact pressure in
sewing the fabric are hardly rendered conductive.
As described above, the conventional dust proof clothes suffer from
the two problems, that is, fabrics used in each portion of the dust
proof clothes cannot achieve good electrical conductance throughout
the fabrics, and upon sewing of the respective portions, electrical
conductance in the sewn portions cannot be stably obtained, so it
is difficult to achieve electrical conductance throughout the dust
proof clothes.
As a method of improving antistatic property, JP60-28546A describes
a method of improving the performance of dissipating static
electricity by raising conductive fibers to the surface of fabric
to form a parallel and check-striped pattern. In this prior art
method, however, the mutual contact between the conductive fibers
formed in the warp and those in the weft are not sufficient, and
the electrical conductance of the resulting fabric in a slanting
direction is hardly obtained. Further, the conductive fibers are
raised to the surface of the fabric, and the conductive fibers have
a larger diameter than that of non-conductive fibers in the base
constituting the fabric, so there is a problem with abrasion
durability.
JP-A 55-135014 describes that for improvement of the electrical
conductance of sewn portions in dust proof clothes, the portions to
be sewn are sewed such that yarn containing conductive fibers as a
part of sewing threads is brought into electrical contact with the
end of conductive fibers mixed in fabric.
In this case, however, electrical contact in the sewn portion is
sometimes deteriorated when drawbacks such as puckering are
appeared in the sewn portion due to repeated wearings and
washings.
JP-A 58-160209 describes clothes in which a conductive material is
arranged at overlap portions or butted portions of fabric having
conductive fibers woven at suitable intervals, so that the
respective portions are an electrical contact with one another. In
this case, however, there is an economical problem because the
conductive material should be arranged at the cloth overlap
portions or the butted portions, and there is a further problem
with the durability of the conductive material itself to be
arranged.
OBJECT OF THE INVENTION
The object of the present invention is to provide fabrics excellent
in conductivity and antistatic property as well as dust proof
clothes being electrically conductive throughout the dust proof
clothes and further excellent in durability and antistatic
property, to solve the problems described above.
SUMMARY OF THE INVENTION
First, the present invention resides in fabrics comprising warps
and/or wefts containing electrically conductive yarn at intervals,
characterized in that the electrically conductive yarn is
structured by covering synthetic filament yarn as the core with
conductive bicomponent fibers.
Second, the present invention resides in the above-described
fabrics wherein the conductive yarn is structured by
double-covering synthetic filament yarn as the core with conductive
bicomponent fibers.
Thirdly, the present invention resides in the above-described
fabrics wherein the conductive yarn is contained in both of the
warps and wefts at intervals thereof and that in one is structured
by double-covering synthetic filament yarn as the core with
conductive bicomponent fibers and the other is structured by
single-covering synthetic filament yarn as the core with conductive
bicomponent fibers.
Fourthly, the present invention resides in the above-described
fabrics wherein the conductive yarn is contained in both of the
warps and wefts at intervals thereof and that in one is structured
by double-covering synthetic filament yarn as the core with
conductive bicomponent fibers and the other is double-twisted yarn
composed of synthetic filament yarn and conductive bicomponent
fibers.
Fifthly, the present invention resides in the above-described
fabrics wherein the degree of coverage of the conductive
bicomponent fiber in the conductive yarn is 20 to 70%.
Sixthly, the present invention resides in the above-described
fabrics wherein the conductive bicomponent fiber comprises carbon
and the electric resistance thereof is 10.sup.6 -10.sup.9
.OMEGA./cm.
Seventhly, the present invention resides in the above-described
fabrics wherein the conductive bicomponent fiber is obtained by
bicomponent spinning a non-conductive base polymer and a matrix
polymer containing carbon as conductive component such that at
least a part of the latter is exposed to the surface of fibers.
Eighthly, the present invention resides in dust proof clothes
comprising the above-described fabrics.
Ninethly, the present invention resides in the above-described dust
proof clothes comprising fabrics stitched together using sewing
thread containing 30 to 100% by weight of conductive bicomponent
fibers containing carbon and having an electric resistance of
10.sup.6 -10.sup.9 .OMEGA./cm.
Tenthly, the present invention resides in the above-described dust
proof clothes wherein conductive fibers containing in the sewing
thread are obtained by bicomponent-spinning a non-conductive base
polymer and a matrix polymer containing carbon as conductive
component such that at least a part of the latter is exposed to the
surface of fibers.
Eleventhly, the present invention resides in the above-described
dust proof clothes wherein the resistance of a portion including
sewn portions is 10.sup.9.OMEGA. or less.
DETAILED DESCRIPTION OF THE INVENTION
In the fabrics of the invention, the conductive yarn used as the
warp and weft is structured by covering synthetic filament yarn as
the core with conductive bicomponent fibers, and in particular the
conductive yarn used as at least one of the warp and weft is
preferably structured by double-covering synthetic filament yarn as
the core with conductive bicomponent fibers, and particularly
preferably the conductive yarn used as at least one of the warp and
weft is structured by double-covering synthetic filament yarn as
the core with conductive bicomponent fibers while the other is
structured by single-covering synthetic filament yarn as the core
with conductive bicomponent fibers.
Synthetic filament yarn used as the core of the conductive yarn may
be substantially the same as that constituting the base of fabrics
for clothes. Specific examples of its materials include polyester
(polyethylene terephthalate etc.), polyamide (nylon 6, nylon 66,
etc.) etc., among which the polyester is most preferable for
chemical stability and handling property. For example, polyester
filament yarn or polyeser finished yarn such as polyester false
twisted yarn, which has 0.1 to 5 denier in finesses as single fiber
and 50 to 200 denier in total fineness, is preferably used.
The conductive fibers for covering (non-conductive) synthetic
filament yarn includes yarns comprising metal-coated synthetic
filaments bicomponent fibers obtained by bicomponent spinning a
base polymer as fiber substrate and a conductive polymer having
fine particles of a conductive material such as carbon, metal or
metal compound dispersed in a matrix polymer. The latter
bicomponent spun fiber using carbon as a conductive material is
most preferable.
Insofar as a part of (the conductive polymer containing) the
conductive material in the bicomponent fiber is exposed to the
surface, the sectional shape are not particularly limited. One
example of its sectional shape is shown in FIG. 1. In FIG. 1, 1 is
a base polymer (non-conductive polymer) layer and 2 is an
electrically conductive polymer layer.
By way of example, the conductive bicomponent fibers of 1 to 5
denier in finesses as single fiber or of 10 to 200 denier
preferably 10 to 100 denier in total fineness is preferably used.
It is preferable for friction resistance that conductive
bicomponent fiber has a finesses not more than that of yarn
constituting the base of textile, and preferably, the resistance
thereof is usually 10.sup.9 .OMEGA./cm or less, particularly
10.sup.8 .OMEGA./cm or less.
Conductive yarn is produced by covering preferably double-covering
the (non-conductive) synthetic filament yarn as the core with the
conductive bicomponent fibers.
The degree of coverage of the conductive fiber in the conductive
yarn in the double-covering structure is the proportion of the
conductive fiber when viewed from the side of the conductive yarn
as shown in FIG. 2, and this degree is shown in the following
formula.
Degree (%) of coverage of conductive fiber=area of conductive
fiber/area of conductive yarn.times.100.
Although the degree of coverage of the conductive fiber is
preferably as high as possible, the degree of coverage of the
conductive fiber is preferably 20 to 70% in consideration of the
processability, manufacturing, costs, conductivity etc. of the
conductive yarn. Given 20% or less, the effect of electrical
conductance is hardly obtained. In the case of 70% or more,
electrical conductance is hardly obtained. In the case of 70% or
more, electrical conductance can be sufficiently obtained, but even
if the conductive fiber is mixed at such high ratios, no particular
effect cannot be obtained, resulting in higher costs.
The degree of coverage of the conductive fiber in the conductive
yarn is raised in this manner, and the yarn is structured by
double-covering the fiber by simultaneously winding the upper and
lower fiber in the opposite direction to generate friction
resistance by which the covering conductive fiber can be prevented
from slipping at the time of yarn processing and textile
manufacturing.
By use of this structure of conductive yarn, physical properties of
conductive yarn, such as strength etc. can be secured stably.
Further, because the conductive fiber is exposed to the surface of
the yarn, the contact between the conductive fiber of the
conductive yarn inserted into the warp and the conductive fiber of
the conductive yarn inserted into the weft is improved whereby the
electrical conductance of fabrics in all directions including a
slanting direction can be secured. Further, if dust proof clothes
is made of such fabrics, the contact resistance in sewn portions
can be reduced even in contact under low contact pressure in
weaving the fabrics, and thus the electrical conductance among the
sewn portions can be secured. Further, by such structure, fabrics
also excellent in antistatic propeorty can be provided.
Further, the fineness of the conductive yarn is made in the same
range as non-conductive fibers constituting other portions in
fabrics whereby the friction durability can also be improved
without causing the conductive yarn to be protruded from the
fabrics.
The pitch of the conductive yarn to be mixed is 1 yarn/3 cm or
more, preferably 1 yarn/cm, in both the warp and weft
directions.
By such structure, the resistance of fabric measured in the method
shown in FIG. 3 can be 10.sup.6 to 10.sup.9.OMEGA., and in
particular the resistance of fabric in a slanting direction, as
measured in the method shown in FIG. 4, can be 10.sup.6 to
10.sup.9.OMEGA..
Fabrics using the conductive yarn where the degree of coverage of
the conductive fiber is in the above range enable the electrical
conductance of the fabrics in all directions and can simultaneously
reduce resistance stably to secure excellent electrical
control.
By sewing the above fabrics together, it is easy to obtain the
electrical conductance among the sewn portions, and it is possible
to obtain not only fabrics but also dust proof clothes having
electrical conductance throughout the dust proof clothes. Further
the sewn portions have been sewn by use of sewing thread containing
the conductive fiber, whereby stable electrical conductance can be
secured even if puckering occurs after repetition of wearing,
washing etc. In other words, in the case where the electrical
conductance between the adjacent fabrics in deteriorated due to
puckering, the conductive fibers in the fabric and those in the
sewing thread are contacted each other, and as a result stable
electrical conductance can be secured.
The conductive fibers used in the sewn portions include yarns
comprising metal-coated synthetic filaments bicomponent fibers
obtained by bicomponent spinning a base polymer as fiber substrate
and a conductive polymer having fine particles of a conductive
material such as carbon, metal or metal compound dispersed in a
matrix polymer. However, fibers covered with a metal or conductive
fibers comprising a metal as an conductive component have a problem
with durability due to elution or removal of the metal under acidic
or alkaline environments, so it is preferable to use the same
conductive bicomponent spinned yarn as described above for
covering. The latter bicomponent spun fiber using carbon as a
conductive material is most preferable.
Insofar as a part of (the conductive polymer containing) the
conductive material in the bicomponent fiber is exposed to the
surface, the sectional shape are not particularly limited. One
example of its sectional shape is shown in FIG. 1.
By way of example, the conductive bicomponent fibers of 1 to 5
denier in finesses as single fiber or of 10 to 200 denier
preferably 10 to 100 denier in total fineness is preferably used.
The resistance thereof is usually 10.sup.9 .OMEGA./cm or less,
particularly 10.sup.8 .OMEGA./cm or less.
As the sewing thread, it is preferable to use that containing 30 to
100% by weight of such conductive bicomponent fibers. If the
content of the conductive fibers is 30% by weight or less, it is
difficult to obtain a durable electrical conductance stably among
sewn portions.
Conductive yarn having such conductive fibers mixed with
non-conductive fibers can be used as the sewing thread to attain
sewn portions having electrical conductance and being excellent in
durability even if puckering occurs in the sewn portions after
repetition of wearing, washing etc.
The resistance of such conductive yarn is also preferably 10.sup.9
.OMEGA./cm or less, particularly 10.sup.8 .OMEGA./cm or less. The
fineness of the sewing thread is preferably in the range of 180 to
360 denier.
Dust proof clothes produced by sewing the fabrics of the invention
with the sewing thread described above, even upon generation of
static electricity in any portion of the dust proof clothes, can be
easily earthed owing to stable electrical conductance throughout
the fabrics and dust proof clothes,and further are excellent in
durability and antistatic property.
EXAMPLES
Hereinafter, the examples of the invention are described.
Evaluation methods are as follows:
[Surface Resistance of Fabric] (warp direction)
As shown in FIG. 3, a surface resistor (ST-3, SIMUKO) was placed on
a fabric specimen with a width of 5 cm and a length of 5 cm or
more, and its surface resistance was measured. 10 specimens were
measured in warp direction to determine an average.
[Surface Resistance of Fabric] (slanting direction)
Determined as shown in FIG. 4.
[Resistance of Sewing Thread]
As shown in FIG. 5, a surface resistance meter (ST-3, SIMUKO) was
placed quietly on one sewing thread and its resistance was
measured.
10 specimens were measured to determine an average.
[Durability of Weft Yarn]
A fabric sewn by the lock stitch of polyester taffeta (stitch
number: 14) was worn 30 times in accordance with a method described
in method C, JIS L1096 abrasion resistance and the degree of
abrasion was judged with the eye (Wearing Ring No. CS10, a loading
of 250 gf).
(Judgment Criteria) Good: The sewing thread is slightly damaged.
Medium: The sewing thread is considerably damaged. Bad: The sewing
thread is cut.
[Chemical Durability of Sewing Thread]
Conducted in accordance with the Cas test described in JIS H8502
(method of tesing corrosion resistance of plating). A specimen was
sewn by the lock stitch of 1 dm.sup.2 polyester taffeta by passing
sewing thread therethrough at a stitch number of 14.
The test time was 24 hours and the specimen was evaluated according
to the following criteria. Good: Corrosion is not observed in the
portion of conductive fiber. Bad: Corrosion is observed in the
portion of conductive fiber.
[Resistance in Sewn Portions]
As shown in FIG. 6, two textiles were wound and sewn such that the
angle (.theta.) between the yarns containing conductive fiber in
the warp was made 5.degree..
A clip electrode was attached to the sewed specimen, and its
resistance was measured in SIMUKO surface resistance meter
ST-3.
[Resistance of Dust Proof Clothes]
As shown in FIG. 7, a clip electrode was attached to sewed clothes
to determine resistance.
[Fabric Durability]
A fabric was worn 5000 times in accordance with E method described
in JIS L1096 abrasion resistance and the degree of abrasion was
judged with eye.
Example 1
Polyester filament yarn 75d-36f was used as the warp and polyester
false twisted yarn 100d-48f was used as the weft to form a textile
as the base. As conductive yarn in the warp, polyester filament
yarn 30d-12f was covered by S-twist with Beltron B31 (Kanebo, Ltd.)
20d-6f at 600 T/m and further covered thereon by Z-twist with
Beltron B31 (Kanebo, Ltd.) 20d-6f at 480 T/m whereby conductive
yarn constructed by double-covering wherein the degree of coverage
of the conductive fiber was 65% was prepared. The resulting yarns
were inserted at the ratio of 1:30 into the yarns of the above
textile. As conductive yarn in the weft, covered thread prepared by
single-covering polyester filament yarn 50d-24f by S-twist with
Beltron B31 (Kanebo, Ltd.) 20d-6f at 600 T/m wherein the degree of
coverage of the conductive fiber was 30%, was also inserted at the
ratio of 1:20 into the yarns of the above textile, whereby plain
weave fabric having a warp density of 160 yarns/inch. and a weft
density of 105 yarns/inch was produced. Separately, one thread of
polyester filament yarn 40d-18f and two threads of Beltron B31
(Kanebo, Ltd.) 20d-6f were twisted together by S-twist at 600 T/m
to give a string, and 3 strings thus prepared were twisted together
by Z-twist at 480 T/m to prepare sewing thread. Dust proof clothes
were produced by winding and sewing the above plain weave fabric
with the sewing thread. The performance thereof is shown in Tables
1, 2, 3 and 4.
Example 2
Polyester filament yarn 75d-36f was used as the warp and polyester
false twisted yarn 100d-48f was used as the weft to form a textile
as the base. As conductive yarn in the warp, polyester filament
yarn 30d-12f was covered by S-twist with Beltron B31 (Kanebo, Ltd.)
20d-6f at 600 T/m and further covered thereon by Z-twist with
Beltron B31 (Kanebo, Ltd.) 20d-6f at 480 T/m whereby conductive
yarn constructed by double-covering wherein the degree of coverage
of the conductive fiber was 65% was prepared. The resulting yarns
were inserted at the ratio of 1:30 into the yarns of the above
textile. As conductive yarn in the weft, single-covered thread
prepared by covering polyester filament yarn 75d-36f by S-twist
with Beltron B31 (Kanebo, Ltd.) 20d-6f at 600 T/m wherein the
degree of coverage of the conductive fiber was 28%, was also
inserted at the ratio of 1:20 into the yarns of the above textile,
whereby 2/3 twill fabric having a warp density of 160 yarns/inch
and a weft density of 110 yarns/inch was produced. Separately, one
thread of polyester filament yarn 40d.varies.18f and two threads of
Beltron B31 (Kanebo, Ltd.) 20d-6f were twisted together by S-twist
at 600 T/m to give a string, and 3 strings thus prepared were
twisted together by Z-twist at 480 T/m to prepare sewing thread.
Dust proof clothes were produced by winding and sewing the above
twill fabric with the sewing thread. The performance thereof is
shown in Tables 1 and 2.
Example 3
Polyester filament yarn 75d-36f was used as the warp and polyester
false twisted yarn 100d-48f was used as the weft to form the base
portion of textile. As conductive yarn in the warp, polyester
filament yarn 30d-12f was covered by S-twist with Beltron B31
(Kanebo, Ltd.) 20d-6f at 600 T/m and further covered thereon by
Z-twist with Beltron B31 (Kanebo, Ltd.) 20d-6f at 480 T/m whereby
electrically conductive yarn constructed by double-covering wherein
the degree of coverage of the conductive fiber was 65% was
prepared. The resulting yarns were inserted at the ratio of 1:30
into the yarns of the above textile. As electrically conductive
yarn in the weft, covered thread prepared by twisting finished yarn
75d-36f having polyester temporarily sewn therein and Beltron B31
(Kanebo, Ltd.) 20d-6f together by S-twist at 600 T/m wherein the
degree of coverage of the conductive fiber was 26%, was also
inserted at the ratio of 1:20 into the yarns of the above textile,
whereby plain weave fabric having a warp density of 160 yarns/inch
and a weft density of 85 yarns/inch was produced. Separately, one
thread of polyester filament yarn 40d-18f and two threads of
Beltron B31 (Kanebo, Ltd.) 20d-6f were twisted together by S-twist
at 600 T/m to give a string, and 3 strings thus prepared were
twisted together by Z-twist at 480 T/m to prepare sewing thread.
Dust proof clothes were produced by winding and sewing the above
plain weave fabric with the sewing thread. The performance thereof
is shown in Tables 1 and 2.
Comparative Example 1
Polyester filament yarn 75d-36f was used as the warp and polyester
false twisted yarn 75d-36f was used as the weft to form a textile.
As conductive yarn in the warp, polyester filament yarn 30d-12f was
covered by S-twist with Beltron B31 (Kanebo, Ltd.) 20d-6f at 600
T/m and further covered thereon by Z-twist with Beltron B31
(Kanebo, Ltd.) 20d-6f at 480 T/m whereby conductive yarn
constructed by double-covering wherein the degree of coverage of
the conductive fiber was 65% was prepared, and the resulting yarns
were inserted at the ratio of 1:30 into the yarns of the above
textile, whereby plain weave fabric having a warp density of 160
yarns/inch and a weft density of 105 yarns/inch was produced.
Separately, one thread of polyester filament yarn 40d-18f and two
threads of Beltron B31 (Kanebo, Ltd.) 20d-6f were twisted together
by S-twist at 600 T/m to give a string, and 3 strings thus prepared
were twisted together by Z-twist at 480 T/m to prepare sewing
thread. Dust proof clothes were produced by winding and sewing the
above plain weave fabric with the sewing thread. The performance
thereof is shown in Tables 1 and 2.
Comparative Example 2
Polyester filament yarn 75d-36f was used as the warp and polyester
false twisted yarn 75d-36f was used as the weft to form a textile
as the base. As conductive yarn in the warp, polyester filament
yarn 50d-24f was interlaced with Beltron B31 (Kanebo, Ltd.) 20d-6f
whereby conductive yarn wherein the degree of coverage of the
conductive fiber was 15% was prepared. The resulting yarns were
inserted at the ratio of 1:30 into the yarns of the above textile.
As electrically conductive yarn in the weft, covered thread having
a degree of coverage of the conductive fiber of 15% prepared by
covering polyester false twisted yarn 50d-24f interlaced with
Beltron B31 (Kanebo, Ltd.) 20d-6f was also inserted at the ratio of
1:20 into the yarns of the above textile, whereby plain weave
fabric having a warp density of 160 yarns/inch and a weft density
of 105 yarns/inch was produced. Separately, one thread of polyester
filament yarn 40d-18f and two threads of Beltron B31 (Kanebo, Ltd.)
20d-6f were twisted together by S-twist at 600 T/m to give a
string, and 3 strings thus prepared were twisted together by
Z-twist at 480 T/m to prepare sewing thread. Dust proof clothes
were produced by winding and sewing the above plain weave fabric
with the sewing thread. The performance thereof is shown in Tables
1 and 2.
Comparative Example 3
Polyester filament yarn 75d-36f was used as the warp and polyester
false twisted yarn 75d-36f was used as the weft to form a textile
as the base. As electrically conductive yarn in the warp, polyester
filament yarn 100d-48f was twisted by S-twisting at 600 T/m with
Beltron B31 (Kanebo, Ltd.) 20d-6f whereby conductive yarn wherein
the degree of coverage of the conductive fiber was 18% was
prepared. The resulting yarns were inserted at the ratio of 1:30
into the yarns of the above textile. As conductive yarn in the
weft, polyester false twisted yarn 100d-48f was twisted by
S-twisting at 600 T/m with Beltron B31 (Kanebo, Ltd.) 20d-6f
whereby conductive yarn having a degree of coverage of electrically
conductive fiber of 16% was prepared. The resulting yarns were also
inserted at the ratio of 1:20 into the yarns of the above textile,
whereby plain weave fabric having a warp density of 160 yarns/inch
and a weft density of 105 yarns/inch was produced. Separately, one
thread of polyester filament yarn 40d-18f and two threads of
Beltron B31 (Kanebo, Ltd.) 20d-6f were twisted together by S-twist
at 600 T/m to give a string, and 3 strings thus prepared were
twisted together by Z-twist at 480 T/m to prepare sewing thread.
Dust proof clothes were produced by winding and sewing the above
plain weave fabric with the sewing thread. The performance thereof
is shown in Tables 1 and 2.
Comparative Example 4
Polyester filament yarn 75d-24f was twisted by Z-twist at 400 T/m
to give a string, and 3 strings thus obtained were twisted together
by S-twist at 280 T/m to give sewing thread. The fabric in Example
1 was wound and sewn by use of this sewing thread. The performance
thereof is shown in Tables 3 and 4.
Comparative Example 5
Polyester filament yarn 100d-34f was silver-plated and twisted by
S-twist at 600 T/m to give a string, and 3 strings thus obtained
were twisted together by Z-twist at 480 T/m to give sewing thread.
Dust proof clothes were produced by use of this sewing thread. The
performance thereof is shown in Tables 3 and 4.
TABLE 1 Comparative Comparative Comparative Example 1 Example 2
Example 3 Example 1 Example 2 Example 3 Fabrics Yarn in the Warp
PET 75d-36f PET 75d-36f PET 75d-36f PET 75d-36f PET 75d-36f PET
75d-36f base Weft PET 75d-36f PET 100d-45f PET 100d-48f PET 75d-36f
PET 75d-36f PET 75d-36f finished finished finished finished
finished finished yarn yarn yarn yarn yarn yarn Conductive Warp
Double- Double- Double- Double- Interlacing Twisting yarn covering
PET covering PET covering PET covering PET PET 50d-24f PET 100d-48f
30d-12f with 30d-12f with 30d-12f with 30d-12f with with Beltron
with Beltron Beltron B31 Beltron B31 Beltron B31 Beltron 331 B31
20d-6f B31 20d-6f 20d-6f and 20d-6f end 20d-6f and 20d-6f and
Beltron B31 Beltron 331 Beltron B31 Beltron B31 20d-6f 20d-6f
20d-6f 20d-6f Degree of coverage 65% 65% 65% 65% 15% 18% of warp
Weft Single- Single- Twisting PET Interlacing Twisting covering PET
covering PET 75d-36f PET 50d-24f PET 100d-48f 50d-24f 75d-36f
finished with Beltron with Beltron finished finished yarn with B31
20d-6f B31 20d-6f yarn with yarn with Beltron B31 Beltron B31
Beltron B31 20d-6f 20d-6f 20d-6f Degree of coverage 30% 28% 26% 15%
18% of Weft Resistance Weft direction 10.sup.7.5 10.sup.7.5
10.sup.7.7 10.sup.11.0 10.sup.9.7 10.sup.9.1 (.OMEGA.) Slanting
direction 10.sup.7.4 10.sup.7.5 10.sup.7.6 10.sup.11.9 10.sup.12
10.sup.10.8 Fabric good good good good good bad durability
TABLE 2 Comparative Comparative Comparative Example 1 Example 2
Example 3 Example 1 Example 2 Example 3 Sewing thread Yarn 3
strings of one PET 40d-18f twisted with two Beltron B31 20d-6f were
twisted together Resistance (.OMEGA.) 10.sup.7.5 friction
resistance good Chemical durability good Resistance in sewn portion
(.OMEGA.) Initial 10.sup.8.0 10.sup.8.0 10.sup.8.1 10.sup.8.3
10.sup.9.8 10.sup.8.8 After 100-times washing 10.sup.8.1 10.sup.8.1
10.sup.8.2 10.sup.8.3 10.sup.11.8 10.sup.10.9 Resistance of
dust-proof clothes (.OMEGA.) Initial 10.sup.8.0 10.sup.8.0
10.sup.8.1 10.sup.11.3 10.sup.9.9 10.sup.9.3 After 100-times
washing 10.sup.8.0 10.sup.8.1 10.sup.8.2 10.sup.11.7 10.sup.12.0
10.sup.11.3
TABLE 3 Comparative Comparative Example 1 Example 4 Example 5
Fabrics Yarn in the Warp direction PET 75d-36f base Weft direction
PET 75d-36f finished yarn Conductive Warp direction Double-covering
PET 30d-12f with Beltron B31 20d-6f yarn Degree of 65% coverage in
warp direction Weft direction Single-covering PET 30d-24 finished
yarn with Beltron B31 20d-6f Degree of 30% coverage in weft
direction Resistance Warp direction 10.sup.7.2 (.OMEGA.) Slanting
10.sup.7.4 direction
TABLE 4 Comparative Comparative Example 1 Example 4 Example 5
Sewing thread Yarn 3 strings of 3 strings of 3 silver- one PET
40d-18f PET 75d-24f plated PET twisted with were twisted 100d-34f
two Beltron B31 at S 280T/m yarns were 20d-6f were twisted twisted
together together Resistance 10.sup.7.5 10.sup.12.0 10.sup.2.0
(.OMEGA.) Friction good good medium resistance Chemical good good
bad durability Resistance in sewn portion (.OMEGA.) Initial
10.sup.8.0 10.sup.8.0 10.sup.7.7 After 100- 10.sup.8.1 10.sup.12.0
10.sup.10.0 times washing Resistance of dust-proof clothes
(.OMEGA.) Initial 10.sup.8.0 10.sup.8.2 10.sup.8.0 After 100-
10.sup.8.0 10.sup.11.0 10.sup.10.0 times washing
Effects of the Invention
According to the present invention as described above, there can be
provided dust proof clothes capable of efficiently removing static
electricity by use of earthing thereof because the dust proof
clothes are electrically conductive in all directions of fabrics
constituting the dust proof clothes, are excellent in electrical
conductance throughout the dust proof clothes including sewn
portions, and are also excellent in durable electrical conductance
even after repetition of wearing and washing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing one example of the bicomponent
fiber.
FIG. 2 is a sectional view showing the double-covering
structure.
FIG. 3 is a drawing showing the method of measuring the surface
resistance (warp and weft directions) of fabric.
FIG. 4 is a drawing showing the method of measuring the surface
resistance (slanting direction) of fabric.
FIG. 5 is a drawing showing the method of measuring the resistance
of sewing thread.
FIG. 6 is a drawing showing the method of measuring the resistance
of sewn portions.
FIG. 7 is a drawing showing the method of measuring the resistance
of dust proof clothes.
In the drawings, 1 is a base polymer layer, 2 is an electrically
conductive polymer layer, 3 is synthetic filament yarn, 4 is
conductive fiber, 5 is a specimen, 6 is conductive yarn, 7 is a
Resistance measuring apparatus (SIMUKO ST-3), 8 is an electrode, 9
is a sewing thread and 10 is a sewn portion.
* * * * *